Man and Whale - Recommendations

Alt title: Kouchou-sensei to Kujira

If you're looking for manga similar to Man and Whale, you might like these titles.

Noah's Ark

Noah's Ark

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Ookami no Hi: Ezo Ookami Zetsumetsuki

Ookami no Hi: Ezo Ookami Zetsumetsuki

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Sakufuu no Banka

Sakufuu no Banka

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Forest Crisis

Forest Crisis

The forests are in danger! Tina and Tai stumble upon a space pod that has crash-landed onto earth! Befriended by two space aliens, they are unwittingly dragged along on a recovery mission that takes them deep into the forests around the world. However, the kids soon discover that the forests are disappearing! What is going on?! Can they learn the science behind the forests' disappearance and do something before it’s too late?!

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Forest Bear

Forest Bear

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Fourteen

Fourteen

In the future, humanity has destroyed the world’s plant and animal life out of greed and consumption. Meat is biologically created from animal cells to eat, and little remains of what used to be the environment. However, when a mutated, engineered chicken breast morphs into a sentient, vengeful being and human children begin to be born with green hair and spots, it becomes clear that mankind’s fate is anything but secure…

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Shangri-La (Light Novel)

Shangri-La (Light Novel)

In the middle of the 21st century when global warming has turned Tokyo into a tropical city. To reduce the temperature at the heart of the city by 5°C (9°F), the city is being reborn as the world's largest forest city. However, despite the flow of refugees to the new city of Atlas, there are not many residents who can actually live there. Moreover, anti-government guerillas are attempting to stop the forestation.

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Coppelion

Coppelion

In the year 2016, a catastrophic incident at the Odaiba nuclear power plant contaminated the city with radiation and turned Tokyo into a ghost town devoid of life. 20 years later, Japan still struggles with the environmental consequences of that fateful day, and actively looks for survivors using Coppelions: genetically-engineered, radiation-resistant girls who scour the streets when SOS calls occur. With military support and funding to back them up, these young ladies continue to explore Tokyo and discover just who, and what, managed to survive.

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Miyori no Mori

Miyori no Mori

After her parents separated, eleven-year-old Miyori was left in the care of her grandparents who live in the countryside, where she lives a lonely and solemn life. While exploring the woods one day near the village, Miyori comes across a giant cherry tree and meets the spirits of the forest. They tell her that she is the guardian of the forest, a role that Miyori stubbornly does not wish to fill - that is, until she learns that a dam is being built, and it threatens to submerge her home and the home of the spirits! With the help of her new woodland friends and classmates, Miyori hatches a plan to save her new home...

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Sea Tiger

Sea Tiger

Hai Hu is a rich playboy during the day, and at night, he is hero for the people, known as the Sea Tiger. He fights a world renowned organization led by Blue Dream. Blue Dream wants to conquer the world and destroy everything on Earth so that it could be restored into an unpolluted state like it used to be. 

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